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SUMMARY DOCUMENT OUTLINING MAIN ISSUES

UNDERGROUND VIABILITY OF ALTERNATING CURRENT WITH

ISOLATED XLPE CABLE OF A 400 KV DOUBLE CIRCUIT VERY HIGH

VOLTAGE LINE IN THE REGIONS OF GIRONA

(STA. LLOGAIA D’ÀLGUEMA - BESCANÓ SECTION AND RIUDARENES BRANCH)

Title

AUTHOR: BÀRBARA DA SILVA I ROSA

Consultant editor:

C

Revision:

MAY 2010

Date:

Underground feasibility of alternating current with isolated XLPE cable of a 400 kV

double circuit extra high voltage line in the regions of Girona Sintesi_refos_C.doc

Summary document outlining main issues Page 1 of 35

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CONTENTS

MAIN ISSUES ................................................................................................................................................................. 2

1 – SUMMARY ............................................................................................................................................................... 4

2 - INTRODUCTION....................................................................................................................................................... 4

3 - THE TWO APPROACHES: THE REE-DGEM OVERHEAD AND CILMA UNDERGROUND SOLUTIONS....................... 5

4 - FEASIBILITY OF UNDERGROUNDING ...................................................................................................................... 9

4.1 - ELECTRICAL FEASIBILITY ..................................................................................................................................................9 4.2 CONSTRUCTION FEASIBILITY ............................................................................................................................................15 4.3 ENVIRONMENTAL FEASIBILITY ...........................................................................................................................................18 4.4 FEASIBILITY OF TERRITORIAL INTEGRATION ..........................................................................................................................22 4.5 LEGAL FEASIBILITY ..........................................................................................................................................................26 4.6 ECONOMIC FEASIBILITY ..................................................................................................................................................28 4.7 SOCIOPOLITICAL FEASIBILITY............................................................................................................................................30

5 - DGEM COMMISSIONED ASSESSMENT REPORTS.................................................................................................. 31

6 - PROOF ................................................................................................................................................................... 32

7 - CONCLUSIONS ..................................................................................................................................................... 34

8 - LIST OF THE PRINCIPAL EXPERTS AND TECHNICIANS CONSULTED ..................................................................... 34

9 - REFERENCES .......................................................................................................................................................... 36

REFERENCES OF COMPLETED AND ATTACHED STUDIES AND REPORTS................................................................36 RECOMMENDED AND CONSULTED WORKS.............................................................................................................36 OTHER REFERENCES ......................................................................................................................................................37

APPENDIX: SUMMARY TABLE ..................................................................................................................................... 37




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MAIN ISSUES

1. It has been demonstrated that burying the line in the section between Bescanó and Santa Llogaia

d’Àlguema and the Riudarenes branch with the technology that is currently available is completely

technologically possible. CILMA has submitted a solvent expert report drawn up by the PALOP, SL study

workshops. Its members are consultants renowned for their significant portfolio, their international

experience and, above all, the fact that energy companies seek expert advice from them on a recurring

basis.

2. Likewise, when considering direct expenses, burying the EHV (extra high voltage) between Bescanó and

Santa Llogaia d'Àlguema and the Riudarenes branch would only cost a quarter of the direct estimated

price of burying the interconnecting direct current between France and Spain. In other words, completely

burying these sections would cost the approximate price of a single direct-alternating conversion

substation necessary in the underground trans-border section (remember that the interconnecting direct

current would need two substations of this type).

3. If the quantifiable indirect expenses, maintenance and energy loss expenses are considered, burying the

EHV is valued at only double the REE overhead option. These irrefutable results stem from a study ordered

by CILMA and drawn up, among others, by the Faculty of Economic and Business Sciences at the University

of Girona and, in particular, by its dean Dr Anna Garriga i Ripoll.

4. With regard to jurisprudence, quantifying property and building value loss as a consequence of installing

an overhead electrical line has been recognised on various occasions in sentences by courts of justice,

both within the High Court of Justice of Catalonia and the Supreme Court.

5. If indirect expenses are taken into account - such as those called existence and inheritance values,

which, without a doubt, have been considered with regard to interconnection in the Pyrenees - the

underground option is even more cost-effective than the overhead proposal (without estimating other

indirect expenses which are difficult to assess and qualitatively favour burying). The ability to apply the

existence and/or inheritance value concept in environmental assessment processes is founded on that

established in Article 4.1 of the Natural Heritage and Biodiversity State Act and Article 45 of the Spanish

Constitution, as well as scientific doctrine and numerous authors and expert commentators.

6. Environmentally, it is indisputable - and entails common sense - that a studied, carefully designed

underground course on flat terrain, as is the case here, and retracing existing and/or planned infrastructure

in the Girona regions (especially, taking advantage of corresponding service roads), would have a higher

global impact than an overhead route, which would indiscriminately affect scattered urban structures,




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natural areas and an agroforestry landscape of the highest quality. It should be noted that CILMA proposes

a conceptual route proposal, which takes the current situation and existing plans into account with regard

to infrastructure within this region. The ditch or service gallery of the underground is easily integrated into

these infrastructure corridors, meaning social, landscape and environmental impact is minimised or non-

existent. Technical and scientific contributions are not negligible either, with regard to risks and effects on

the health of living beings, provoked by the EHV overhead option. Likewise, initial precautions must prevail

in these cases, just as the Maastricht Treaty and countless institutions indicate.

7. Burying the EHV by using public service or domain areas of other large infrastructure does not entail any

building problems, given that appropriate technology exists for each situation. Likewise, all other buried

infrastructure has largely and systematically overcome possible inconveniences. There would not be any

legal inconveniences either, given that Article 57 of the Electrical Sector Order, Act 54/97, and Article 161

of Royal Decree 1955/2000 indicate that using public service and domain areas to install electrical lines is

preferable and is a priority with regard to privately-owned building distribution.

8. There are similar examples of underground lines throughout the world: for environmental motives

(Denmark, England, Japan, etc.); national security reasons (Kuwait, Afghanistan, United Arab Emirates,

etc.); and also to protect against exposure and harsh weather conditions (France, etc.) The general

tendency points to an increase in underground tunnelling with regard to high voltage lines. Recent storms

and atmospheric phenomena - that will only intensify in the future due to climate change - have fully

demonstrated that overhead lines are vulnerable.

9. When at the environmental assessment stage, it is paramount and legally compulsory to consider all

direct and indirect effects that are provoked within the environment and, in particular, the underground

option. The process of making decisions and authorising the project may be rejected due to an

environmental assessment shortcoming, if the aforementioned issues are not considered. Moreover, the

executive summary of the 2006-2015 Catalonia Energy Plan expressly considers the possibility of carrying

out underground tunnelling on page 37, with regard to EHV or the electrical interconnecting line with

France. It also requires painstaking assessment to guarantee minimum environmental impact.

10. The Generalitat de Catalunya Energy and Mining General Management has not refuted - neither

through ERF- or COEIC-commissioned reports nor through any other entity - any of the elements submitted

by CILMA in its various expert reports. Presented technological and conceptual route solutions have not

been specifically considered either. Such a detailed level in CILMA’s studies with regard to quantifying

expenses or such a concise level in relation to technological solutions for this underground tunnelling

project have not been reached either.




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1 – Summary

Underground tunnelling with an alternating current and an isolated XLPE cable in the Extra high voltage line

- EHV, 400kV double circuit - in the regions of Girona is electronically, constructively, environmentally,

territorially, legally, economically and socio-politically completely viable. Other reports present arguments

and expose findings that have not yet been refuted in a solvent manner.

2 - Introduction

The Consell d’Iniciatives Locals pel Medi Ambient (CILMA) has, since discussions began on the need for an

Extra High Voltage (EHV) transmission line in the counties of Girona, played a central role in the contribution

of technical and economic data. This data, contained in studies commissioned from a number of experts,

along with meetings held with specialists, have enriched an overtly necessary debate. CILMA has

contributed vital information to the deliberation, in an attempt to reach a consensus and a technical

solution that works for and respects everyone.

This document does focus on the discussion regarding the need for the EHV transmission line, but the

viability of completely undergrounding it in the counties of Girona, making use of existing and planned

infrastructure corridors.

With the decision process now in the home stretch, a process for which the DGEM1 has created a work

commission, CILMA wishes to present and defend its undergrounding proposal in a clear, succinct manner,

discussing both its advantages and drawbacks. Above all, however, it wishes to clarify that

undergrounding the 400 kV EHV double-circuit alternating current transmission line between Bescanó and

Santa Llogaia and the Riudarenes branch line, via XLPE insulated cable and existing and/or planned

infrastructure corridors, is not technically unviable nor environmentally incompatible.

This document, therefore, aims to synthesise generated information, document, to the highest degree

possible, the viability of complete undergrounding and defend this alternative against the conventional

overhead solution proposed by Red Eléctrica de España (REE) and essentially defended in the works DGEM

commissioned from COEIC2 and ERF3 [24, 25, 26].

1 Direcció General d’Energia i Mines del Departament d’Energia i Finances de la Generalitat de Catalunya 2 Col·legi Oficial d’Enginyers Industrials de Catalunya 3 Estudi Ramon Folch




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3 - The Two Approaches: The REE-DGEM Overhead and CILMA Underground Solutions

The REE proposes a completely overhead solution, with an approximately 40km 400 kV alternating current

double-circuit (DC) transmission line from the Santa Llogaia converter substation (direct/alternating

current) to Bescanó. It also anticipates an intermediary 400 kV substation in Sant Julià de Ramis (Medinyà),

located some 5 km from the existing 220 kV substation in Juià. The REE is considering dismantling part of the

existing 220 kV EHV DC transmission line between the current Vic substation and the projected Bescanó

substation.

The REE’s proposal for the Riudarenes branch line is identical and consists of an approximately 20km 400 kV

DC branch transmission line.

The REE also anticipates that the 400 kV substations will be conventional AIS (Air Insulated Switchgear)

models, which, according to the MOST Enginyers study [8], have the largest impact and whose erection

entails the greatest amount of occupied space.

The following diagram illustrates the REE’s4 electric power transmission planning proposal:

4 Two FECSA distribution lines have been included in the REE transmission diagram, as the CILMA proposal proposes that these lines be compacted with the EHV transmission line.




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LEGEND:

Voltage:

110/132kV FECSA

220kV REE

400kV

Lines:

Overhead L.

DC Overhead L.

Underground

Underground DC

Substations:

In existence

To be carried out

Figure 1 – REE proposal diagram. Source: Produced in-house.

The solution that the DGEM defends basically consists of the same technical solution as the REE. However, it

proposes that the line route be diverted on several occasions to distance the overhead line from residential

nuclei and isolated dwellings by at least 100m. The proposal also considers the compaction of the EHV

transmission line with the existing Vic-Juià 220 kV double-circuit line and the Juià-Figueres 110-132 kV line

[27].

As per the conclusions made in the Fractàlia report [6], commissioned by CILMA, CILMA’s proposal consists

of undergrounding the alternating current transmission lines being processed with XLPE insulated cable,

eliminating the Sant Julià de Ramis substation and upgrading the existing Juià substation from 220 kV to 400

kV. It also proposes that the current Vic-Bescanó-Juià 220 kV EHV DC transmission line be completely

dismantled between Vic and Juià. To compensate the Juià substation’s 220 kV to 400 kV voltage increase,

it proposes that all installations be compacted using modern Gas Insulated Switchgear, as to avoid

expanding the current substation’s surface area. These Switchgears, described in the MOST Enginyers study

[8], can compact the area required to erect a substation by up to 70%. Moreover, this same report

proposes that the use of this technology expand to the other substations.

As an improvement, CILMA’s proposal also considers the compaction and undergrounding of other high

voltage transmission lines which share the same line route. To be exact, it proposes that the 110/132 kV DC

transmission line which connects the Figueres and Juià substations be compacted, if it cannot be

eliminated altogether.

The following diagram illustrates CILMA’s proposal:




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LEGEND:

Voltage:

110/132kV FECSA

220kV REE

400kV

Lines:

Overhead L.

DC Overhead L.

Underground

Underground DC

Substations:

In existence

To be carried out

Figure 2 – CILMA’s proposal diagram. Source: Produced in-house.

To enhance understanding, the following diagram superposes the CILMA proposal atop the REE proposal:




8

LEGEND:

Voltage:

CILMA’S Proposal:

110/132kV FECSA

220kV REE

400kV

Lines:

Overhead L.

DC Overhead L.

Underground

Underground DC

Substations:

In existence

To be carried out

Figure 3 – Superposition of the CILMA and REE proposals. Source: Produced in-house.

The connection between Santa Llogaia and Bescanó and the Riudarenes branch line must be made with

alternating current due to the intrinsic characteristics of the sections in question and the system’s




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requirements. In undergrounding a 400 kV alternating current transmission line, reactive power

compensation becomes necessary when the length surpasses 10km.

With respect to materials, the studies [6, 7, 10] state that an undergrounding of these characteristics should

employ XLPE (Polyethylene) insulated technology.

As far as line route is concerned, the EHV transmission line will not be underground along the same corridor

as the REE-presented overhead line. Undergrounding cable means that corridors may be minimised and

existing (or, in this case, planned and/or operational) infrastructure may be used, giving the line route

greater flexibility.

4 - Feasibility of undergrounding

Below are set out the various aspects examined by CILMA in order to demonstrate the feasibility of

undergrounding the sections studied. The feasibility of undergrounding must be demonstrated from the

electrical, construction, environmental, territorial integration, legal, economic and socio-political

perspectives.

4.1 - Electrical feasibility

This section is based essentially on the consultancy and report provided by the expert consultants from TEP

[7] and the technical staff at the General Cable Group, Silec Cable [10].

In order to provide proof of electrical feasibility one must first demonstrate that multiple underground

solutions can be achieved equivalent to the overhead solution proposed by REE in terms of the capacity

for energy transmission. In the first part of its report [7], TEP specifies and proposes possible trench solutions

of the "cableway" type which would fulfil REE's electrical requirements, specifying the dimensions for a

trench or tunnel installation. In the same first part of its report TEP has also estimated the needs for reactive

energy compensation in the underground cables and clarified that it is possible to underground the EHV

power line between Santa Llogaia d’Àlguema and Bescanó without the need to create a new

intermediate reactive energy compensation substation in Ramis (Medinyà). Compensation would be

distributed throughout the length, and at the boundary could be distributed at the endpoints of each

underground section.

The so-called "cableway" (as defined by TEP) is the standard cross-section strictly necessary calculated in

such a manner as to allow the underground cables to carry a transmission capacity equivalent to the

planned overhead line (2.441 MVA per circuit, according to the official REE case study, Exp.10.734/2008).

The transmission capacity of an underground cable installation depends essentially on the depth, the

cable arrangement, the distance between phases, the distance between circuits that the cable diameter.

TEP has examined these variables in order to establish solutions which fulfil the desired transmission

capacity. This exercise was performed for trench installations (laid directly or using ducts) and for a tunnel

installation using concrete pipe. TEP concluded, on the basis of the calculations presented in the report [7]




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that in order to offer an equivalent solution two underground cable bundles per circuit would be required

(2 x 2 three-cable bundles = 12 cables) in order to achieve the transmission power required by REE. These

cables would have a copper conductor cross-section of 2500 mm2 and 27 mm XLPE insulation. The outer

diameter of each of the 12 cables required would be 149 mm, taking into consideration the other elements

included in the breakdown in the report [10]. In the technical offer by General Cable [10] we find all these

cable characteristics provided by this supplier. The required cable is presented in Figure 4. We may lastly

state that there do currently exist cables with appropriate characteristics for an underground installation on

this scale. We would not, therefore, foresee problems in the manufacture, supply and installation of the

underground cables.

Figure 4 – SIPRELEC HT 2500 mm² Cu 400 kV Cu wires+ Alu 0.8 G.PEHD: cable recommended by General Cable in [10]. Outer diameter of 149 mm. Source: General Cable [10].

If the chosen option were for a trench with underground cables, in accordance with the report [7] there

would need to be a 50 cm distance between the cables and a 1 m distance between the bundles, taking

into account a horizontal arrangement of 12 cables. If we specify a requirement for 4 m to be maintained

between the circuits (in order to guarantee their independence in the event of maintenance or incidents),

and allowing for a safety distance of 1 m on each side, TEP concludes that the minimum width of the

trench cableway would be 12 m. TEP took into consideration a conservative trench depth of 2.0 m at the

centrepoint of the cables5, while at all times erring on the side of caution. The recommendation would be

to install the underground cables in ducts, since the increase in cost is insignificant in comparison with the

potential benefits (installation and maintenance). These ducts would have a diameter of approximately 30

cm according to the reports [9] and [10].

According to the study [9], if one planned for an underground cable solution installed in a tunnel, the pipe

would require internal dimensions of 2.20 m in height and approximately 2.10 m in width. The proposal

5 Consultation of the specialist bibliography held by the Conseil International des Grands Réseaux Electriques (CIGRE) has established that shallower trench depths have been used in similar circumstances, generally 1.5 m. An adjustment of the depth would facilitate execution and reduce the direct costs of the civil engineering involved in a trench solution. In any event, this aspect would need to be specified in the construction plans. Likewise, one could examine in greater detail a reduction in the distances taken into consideration without impacting on transmission capacity, such as the lateral safety distances (1m x 2) and the separation between the two independent circuits (4 m).




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would be for the underground cables to be arranged vertically within the pitch, with one circuit (two

bundles) on each side. Within one single circuit the bundles would be separated by a 10 cm thick wall, and

both circuits would be positioned 10 cm away from the inner walls of the tunnel. The central part of the

pipe would be arranged as an access zone for personnel, in accordance with the applicable regulations.

Figure 5 sets out the described systems proposed for the arrangement of the underground cables in a

trench or tunnel.

d1 = 50 cm; d2 = 1 m; d3 = 4 m; d4 = 1 m

Figure 5 – Layouts for arrangement of the 2 bundles per circuit examined in [7] for an underground cable trench solution arranged horizontally, and for a tunnel with underground cables arranged vertically. Source: Produced in-house.

The General Cable Group meanwhile also examined an underground EHV power line trench installation

with ducts, submitting a preliminary technical offer (see report [10]). It defines the jointing bays required

every 500 m ( )6 the layout dimensions being 15 m x 2 m; this essentially coincides with the information

provided by TEP.

General Cable also describes the specifications of the underground cable terminals, the joints, the ground

connection boxes and the required cross bonding7. Below is presented the layout of the jointing bays

which it will be necessary to be able to access and open, and where the cross bonding would take place.

These are all underground installations.

6 According to the report [7] issued by TEP, this distance could be increased up to 800 m in special cases. The reels would need to be transported by means of a truck with trailer in order to maximise the distance. 7 Cross bonding involves the crossover of the sheathes between the three cables in the bundle.




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Figure 6 – Cross bonding layout in an inspection box. Source: General Cable [10]. Photo 1 – Example of jointing bay. Source [18].

A trefoil arrangement minimises the electromagnetic effects in the three-cable bundles. Because the

distance between the phases is reduced, this then reduces the maximum thermal capacity, while

minimising the magnetic fields and reducing the width of the cableway to 8 m. TEP concluded that this

solution would be possible up to a power of 970 MVA per three-cable bundle (1940 MVA per circuit), in

other words it would achieve only 80% of the capacity required by REE in the official documentation

consulted.

This solution would, however, be possible if REE were to adjust the required transmission capacity.

According to the report [7] even an overhead power line (for example a cardinal quadruplex) would

struggle to meet this capacity, since with the same voltage drop the acceptable load for the overhead

power line would be lower than an underground cable. The REE conditions in terms of transmission

capacity demand that equivalent solutions using underground cables must be much more conservative,

as it is the maximum thermal capacity which dictates the design of the underground solution, as opposed

to the case of an overhead solution (where the voltage drop limits the design).

Figure 7– Horizontal arrangement of three cables (in this case half a circuit) on the right, and trefoil arrangement on the left. Source: CIGRE [5]

Another aspect to take into consideration in alternating current underground power lines is the reduction in

usable current in the underground cables because of the capacitive currents between the sheath and the

conductor. For long power lines (over 10 km) this effect must be compensated for, with compensation

reactances being installed to cancel out the induced effects. According to TEP's calculations, it is

estimated that the total power to be compensated would be 12.5 MVAr/km per three cables, in other

words approximately 800 MVAr to be compensated at the Santa Llogaia and Bescanó substation, and 600

MVAr at the Juià or Riudarenes substation. In the interest of prudence, and while offering no guarantees in

terms of the REE operating conditions, TEP proposed that compensation reactances be distributed at least

equally at the end-point substations for each of the underground sections. This would also mean allowing




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for compensation of approximately 600 MVAr at a compensation substation at the start of the Riudarenes

underground branch.

The compensation proposal examined is illustrated in Figure 8.

Figure 8 – Proposed reactance compensation system. Source: Produced in-house.

According to the report [10], the increase in space required by reactive energy compensation would be

approximately 1500 to 2000 m2, representing an increase of at the most 5% in the surface area of the

planned transformation substations. A part of this surface area, and potentially all of it, could be enclosed

through the installation of appropriate technology.

Photo 2– Example of a 400 kV, 160 MVAr three-phase reactor measuring 9x6x9 m and weighing 160 tonnes. It is estimated that between 3 and 4 reactors of this type would be required per circuit and per end-point substation. Source: [16]

Other conclusions of interest reached by TEP are as follows:

under maximum load conditions the losses in the overhead solution are three times higher than in the

underground solution with cables in a trench;

in the event of a tunnel cable installation forced ventilation would be required only if the thermal load

exceeds 82% of the capacity of the underground cables as a whole.




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Taking into consideration the lengths involved, the most important effect requiring compensation would be

the Ferranti effect, in other words an excessive increase in tension under certain grid operation conditions.

Allowance must be made for appropriate voltage arresters at the transition points.

Any faults which could potentially occur in the case of an underground solution would most likely be

located in the jointing bays, making their repair and location simpler. However, it must be borne in mind

that the repair time could be greater than one day, and that during this period the faulty circuit would be

unavailable. It is worth pointing out that underground cables are not subject to the temporary faults to

which overhead power lines are constantly prone, even taking into consideration their automatic

reconnection.

Regarding the proposal to install substations with GIS technology in accordance with the report [8], TEP

highlights the fact that the technology exists to build substations with protection and manoeuvring

switchgear in the sub-soil for this voltage level, and that there would be no technical reason why this

solution could not be adopted. Such technology would, among other aspects, allow for compensation of

the fact that the current 400kV Juià substation would need to be expanded in order to allow the Ramis

substation to be eliminated. According to the report [8], by combining the facilities and improving the

technology of the current Juià substation, the new 400 kV switchyard could be installed without the need

for expansion. Meanwhile, the visual impact of the Juià substation could be drastically reduced if the yards

were installed underground, or at least enclosed. An illustration of the possible appearance of these

substations presented below, using the example of an enclosed extra-high voltage substation using GIS

technology:

Photo 3 – Baquèira Substation (Endesa) in the Vall d’Aran, located at the foot of the ski slopes and fully integrated. Source: JT08 CIGRÉ

There are many examples of GIS substations, including 220 kV and 400 kV facilities worldwide. Although

substations are mainly installed underground in urban areas, the system is also adopted in environmentally

sensitive rural areas, and generally in association with underground cabling (see report [six]).

Regarding the undergrounding of the Santa Llogaia – Juià - Bescanó section and taking into account the

direct/alternating current (DC/AC) conversion plant for the Santa Llogaia d’Àlguema substation, it is felt

that the conversion would not be incompatible with the underground AC installation proposed by CILMA. It

should be mentioned that there exist electronic devices which can improve the capacity temporarily to

provide the short-circuit power which may be required. The type of device depends on the technology

employed for the DC/AC conversion. There currently exist elements to control stability, to direct power,

convert the phase angle in terms of stability, control the voltage, the frequency and the energy flux

(FACTS).




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4.2 Construction feasibility

This section is essentially based on the study submitted by the civil engineering consultancy MOST Enginyers,

SL [9].

In an underground solution civil engineering is of supreme importance. Apart from the space required in

order to route the underground cables, additional corridors must also be found in order to perform the

construction work and provide permanent access to the jointing bays. Definition is here more subjective,

and essentially depends on the operating requirements and the type and methodology of installation. The

widths required may be reduced by employing appropriate construction methods. The main principle

applied in the proposal involves installation of the EHV underground cables in a tunnel on publicly owned

land following infrastructure corridors. This would mean that no expropriation would be required, as the

publicly owned infrastructure right-of-way already exists. In this regard, the proposal is to underground the

section Santa Llogaia – Juià – Bescanó by tunnel.

As for the Riudarenes branch, it is proposed that this be installed partially by trench, using ducts, since for a

distance of some 5 km it will not follow any planned infrastructure route. Photo 4 provides examples of the

two main installation solutions for the underground EHV power line.

Photo 4 – Examples of installation by tunnel and in an underground cable trench in urban and rural areas, involving similar underground cables. Source: [13], [15] and [18].

Both the tunnel solution and the solution using concrete ducts in a ditch enjoy considerable mechanical

resistance capable of withstanding heavy wheeled traffic and allowing the civil engineering to be

performed separately from the remaining operations (laying of underground cables and splicing in the

jointing bays). This means that once the civil engineering has been performed the cables could be laid

from the jointing bays, without the need to lay the cables with the trenches open, in parallel corridors.

There are construction methods suited to all foreseeable situations, such as crossing a roadway or the use

of a bridge to transport cables. Particular mention should be made of the developments being seen in the

horizontal directed drilling method, which would be ideal for the Rivers Fluvià and Ter, the AP-7 and A-2

highways, along with oleodynamic pressure, suitable for crossing over the high-speed train lines and the

inland rail corridor. Other methods employed in tunnelling could also be considered on a more limited

basis. As an alternative, the cables could be attached to the underside of the decks of existing bridges

and viaducts where it proves necessary to cross over a water course, roadway or railway line (see Photo 5).




16

Photo 5 – Figure of the techniques to be employed in an underground installation on this scale. Left to right: Horizontal directed drilling, oleodynamic pressure, use of bridges and viaducts, and lastly tunnelling. Source: [13], [16] and [14].

According to the manufacturer General Cable and the specialist bibliography consulted, it is technically

possible to install underground cables in vertical shafts, in areas with considerable inclines or abrupt

embankments, by taking the standard precautions for such circumstances.

Consideration should be given to the possibility of sharing the rights of way covered by the range of existing

infrastructure (high-speed train, AP-7, A-2, C-25 highways, etc.). It may also be possible to make use of

protected areas, in particular publicly owned land, in order to eliminate the cost of expropriation and

compensation, limit land use, and ultimately produce a more efficient project. In order to achieve this the

corresponding authorisations as established in law would need to be requested from the relevant public

authorities. The report [11] supports the legal feasibility of the underground proposal running through

publicly owned land or infrastructure rights-of-way. In the case of highways, authorisation for publicly

owned land may be granted by the Ministry and is provided for on an exceptional basis. It would

meanwhile seem clear that there would be no problem in installing the underground EHV power line along

the right-of-way zone, given that the works are fully compatible with road safety.

According to the High Voltage Regulations, and taking into consideration the proposed solutions, the width

of right-of-way required by an underground trench installation would be approximately 16 m, while in the

case of a tunnel this would have to be specified by REE. It is expected that the right-of-way required for a

tunnel solution would involve a width of around 8 m at the most. The tunnel would fit perfectly well within

the publicly owned land along, for example, the AP-7 motorway, which is precisely 8 m, in accordance

with the current Highways Act.

From the construction perspective, it has been concluded that:

- There are plentiful construction methodologies which could be used to install the EHV underground in the

districts of Girona province;

- The existing technologies capable of overcoming the individual obstacles (rivers, roadways, other

infrastructure facilities, etc.) without using an open trench are well known and are the same as those

employed for the installation of numerous other underground utilities; Each obstacle and soil type has its

own ideally suited technique;

- There exist infrastructure corridors which could be exploited, such as those of the high-speed train line, the

AP-7, C-25 and A-2 highways and the inland rail corridor;

- The width of land required for open undergrounding work may be estimated at between 10 and 15 m,

with a right-of-way of between 8 and 16 m in width;




17

Below are presented the standard trenches designed on the basis of the calculations and observations in

the TEP reports [7], for both trenches (Figure 9) and tunnels (Figure 10):

Option 1 – with flush concrete and pipes

Figure 9– Standard trench proposed for a trench installation with 30 cm diameter ducts, in accordance with reports [7] and [9]. Source: report [9].

Source: Produced in-house

Figure 10- Standard trench proposed for a tunnel installation with and without bracing, in accordance with report [7] and [9]. Source: report [9].

It should be pointed out that the impact caused by the undergrounding of a utility of this type is

concentrated mainly during the civil engineering work. Below we illustrate the contemporary visual impact

of undergrounding the EHV power line (see Photo 6 and




18

Photo 7).

Photo 6 – Photomontage illustrating the temporary impact of undergrounding the EHV line. Before, immediately after the work and two years later. Source: Produced in-house.

Photo 7 – Newby - Nunthorpe EHV power line, installed by trench in rural area (England). During building work, shortly afterwards and 18 months after the work was completed. Source: [17].

4.3 Environmental feasibility

From the environmental perspective, feasibility is supported by the report issued by the physicist Mr. Dépris

[4], indicating the main environmental impacts caused by an EHV power line of this type, and the report

issued by Fractàlia-La Copa [3], of particular value in assessing the impact of the overhead branch in

Riudaranes as proposed by REE. It is clear that the underground solution offers environmental benefits,

since ultimately this is the main argument behind it: undergrounding is employed worldwide in order to

avoid the impact of pylons.

The report [4] highlights above all the environmental drawbacks of overhead power lines, such as the risks

of electrocution and electrification, potential accidents and incidents involving property and persons,

vulnerability to inclement weather, accident, vandalism and terrorism. It also makes mention of the

increased risk of fires associated with overhead power lines in wooded areas, of particular importance

given the present climatic change and instability. The underground cable solution, meanwhile, is

practically invulnerable from these perspectives, and could even be used as a fire gap to prevent the

spread of forest fires. The exposure of overhead power lines represents their major drawback and

exemplifies their vulnerability and also hazardousness.

Mr. Dépris explains in [4] that ionisation of the air (the so-called corona effect) has harmful repercussions

for health as a result of noise pollution and underlying chemical pollution caused by extra-high-voltage

overhead power lines.

To a great extent the corridor left by the undergrounding of the cables could be used in order to

supplement Girona's network of greenways, and act as a multi-functional element improving connections.

This would thus give the right-of-way along which the cable ducts run a social linking function, encouraging




19

travel on foot and by bicycle. The corridor left by the undergrounding operation could also be used as

pasture, or even as a service route blending in perfectly with the agricultural and forestry mosaic of the

land affected. The same corridor would provide access to the jointing bays, since the chosen installation

methods would withstand such loads. A good design, complying with surface electromagnetic field

limitations, would make the aforementioned uses compatible with the corridor left by the EHV power line. It

should be remembered that in urban areas EHV lines generally pass below streets with high levels of traffic

flow.

According to the sources and various experts consulted, there would be no need for the corridor along

which the underground cables pass to be enclosed or tarmacked.

As for the Santa Llogaia - Bescanó section, which runs in the main through the districts of Alt Empordà, Pla

de l’Estany and Gironès, the visual impact of 400 kV DC pylons would clearly be enormous, and it should

not be forgotten that the main driving force behind the local economy is tourism-related.

The conclusion presented in the report [3] is that a wide range of an environments in the area affected by

the overhead power line proposed by REE in the Riudarenes branch would be affected, both

Mediterranean landscapes and wetlands, representing a mosaic of habitats of particular importance

within the Mediterranean context. The area is home to habitats of non-priority community interest, such as

woodlands of cork oaks, holm oaks, Aleppo pines and chestnuts, along with habitats of a Central

European nature, such as oak forests, and aquatic environments; habitats of priority community interest,

such as alder groves, found along all the watercourses here; as well as habitats which are rare in

Catalonia, such as the groves of African oak. All these environments could be impacted by the planned

overhead power line, either through their destruction, damage or collapse in the case of river

environments, through the accumulation of materials caused by the installation of the pylons. Fauna here is

represented by all animal groups, and practically all of them feature protected species of bird life, both

nesting and migratory. Particular mention should be made of the impact on a migratory route employed

by numerous species, including kestrels, harriers, swifts, swallows, martins and others. In the area examined

in the report [3] there are various breeding grounds, such as Puigsardina, used by the short-toed eagle

(Circaetus gallicus), the Serra del Bagissot, used by the Peregrine falcon (Falco peregrinus) and the eagle

owl (Bubo bubo), along with other surrounding areas used as breeding grounds by the honey buzzard

(Pernis apivorus) and the hobby (Falco subbuteo). There are also other species which nest in the inland

Guilleries district, but which make territorial use of the area under study, such as the griffon vulture (Gyps

fulvus) and the booted eagle (Hieraaetus pennatus). In terms of heritage, the main site affected by the

Riudarenes branch of the EHV line is the Argimon Sanctuary, built close to the ruins of the mediaeval

Argimon Castle and the Esparra Tower.




20

Photo 8 – Views of the Argimon and Esparra Sanctuaries. Source: various.

This mosaic of habitats undoubtedly has considerable existential and landscape value, as great as that of

the Pyrenees. In the Baixàs - Santa Llogaia interconnection section the natural environment was presented

as the reason for the exorbitant increase in the cost involved, giving rise to an underground solution at a

cost of €20M/km (including the DC/AC conversion substations). This evaluation is detailed further on in the

section covering economic feasibility.

In terms of the environment, the undergrounding of the EHV may be summarised in terms of the impact of

the civil engineering work, as with any other infrastructure, an impact which is in any event moderate and

will depend on the installation methods employed, and which is temporary and reversible, as

demonstrated by Photo 6. Photo 9 and Illustration 1likewise demonstrate the way in which

undergrounding can be incorporated within the landscape by applying compensation measures to

improve and enrich the natural setting.

Photo 9 – Photomontages illustrating the landscaping of the underground EHV power line against a level mosaic landscape. Before, during and two years after the work. Source: Produced in-house.

Illustration 1– Drawing of the inthouse.

EHV line

egration of the underground EHV power line against a mosaic landscape. Produced: in-




21

With regard to the corrective measures to be taken into consideration during execution of the

undergrounding work, they should be essentially underpin landscape integration, although the route taken

by the infrastructure minimises the need for this. Attention will also need to be paid to integration of all

elements required for the underground installation (tunnel ventilation, compensation substations, etc.),

masking the layout of the corridor as it passes through wooded areas, maintaining the relief and adopting

appropriate measures in order, for example, to avoid any possible soil erosion during construction work.

As for the underground route through forested areas, this is felt acceptable provided that there are no

more suitable corridors and that advantage is taken of ridges, crops, forest tracks, etc. Below is illustrated

the integration of the underground EHV line along a forest track. This integration is illustrated below (Photo

10 and Illustration 2) .

Photo 10 – Photomontages illustrating the landscaping of the underground EHV line along forest tracks. Before, during and two years after the work. Source: Produced in-house.

Illustration 2 – Drawing of the integration of the house.

As for the no less insignificant effects of

Bardasano Rubio, consideration must unq

the Maastricht Treaty, leading to the jud

health. Mr José Lluis Bardasano Rubio enjo

given his long track record in the sphere. H

in medicine and surgery, but is a specialis

electromagnetism and Health Sciences F

same area, as well as being an adviser to

EVH line

underground EHV power line against a mosaic landscape. Produced: in-

EHV power lines on health, according to [28] by Mr. José Lluis

uestionably be given to the principle of prudence, as ratified by

gement that the underground option is indeed less harmful to

ys indisputable experience and technical standing in this regard,

e not only holds a doctorate in biological science and a degree

t in bio-electromagnetism and the President of the European Bio-

oundation, along with other associations and foundations in the

the Parliamentary Environmental Committee for this issue. In his




22

report [28] he makes it quite clear that exposure to overhead EHV power lines is harmful to the health of

living beings, and concludes by stating that undergrounding serves to minimise these effects.

4.4 Feasibility of territorial integration With regard to territorial integration, one possible route is proposed, following the available infrastructure corridors in both the Santa Llogaia - Bescanó sections and the Riudarenes branch (see Illustration 3).

The aim here is to illustrate the opportunities for using existing infrastructure corridors and to identify these by

section. We are nonetheless aware of the need to analyse in detail aspects such as inclines, impacts,

planning, geology, factory works, etc. The attempt with regard to these elements has been to establish

more precise figures of the cost of undergrounding, taking into consideration the underground cable

lengths defined by an outline and standard cross-sections defined in accordance with electrical

calculations and civil engineering requirements.

The Santa Llogaia – Bescanó section would essentially follow the A-2 highway as far as Vilafresser, and the

dual-lane Bordils, Celrà and Medinyà bypass practically as far as the Juià substation. From Vilafresser to Salt

it would more or less follow the corridor of the AP-7 Highway combined with the A-2 and from there as far

as the Bescanó substation the underground cables could be combined with the future N-141e (Brugent-Ter

corridor) which is currently in the planning phase for the Bescanó-Salt section. One proposed improvement

would involve combining and undergrounding the 132 KV DC line together with the EHV between Figueres

and Juià. Undergrounding the EHV line by tunnel would, meanwhile, allow for the elimination of multiple

trenches and the right-of-way involved in the case of combination with other lines. The proposal is thus to

dismantle the current overhead 132 kV Figueres-Juià DC line, which currently affects some 20 km of land.

The social benefits of dismantling this line compensate for the costs of dismantling and undergrounding, if

one takes into consideration the fact that the territorial impact is just 50% of that of a 400 kV line.

As for the undergrounding of the Riudarenes branch, the initial proposal would take advantage of the

corridors employed by the C-25 highway, the high-speed train line and the inland train corridor. In order to

link up with the inland train corridor and C-25 from the Vic/Sentmenat - Bescanó EHV overhead line, the

plan is for an underground trench section using ducts, covering approximately 5 km and taking advantage

of forest tracks, ridges and deforested paths along which the overhead distribution lines supplying isolated

farmhouses currently run. These could also be combined with the EHV line. It should be remembered that

these ridges represent particularly sensitive natural areas in terms of high forest fire risk. By taking advantage

of the existing pastures and former cultivated land, along with the many forest tracks and access routes in

this area, this would give a continuous and a irregular strip of open spaces in the form of a thinned forest.

Such a system would, meanwhile, create a series of ecotones (or boundary spaces), increasing the

biological diversity and richness of the surrounding landscape. Having reached the inland rail corridor the

route would then follow this for a couple of kilometres, before linking up with the C-25 as far as Santa

Margarida. From there it would run along the route of the high-speed train line as far as the Riudarenes




23

substation. The proposal, in order to take advantage of the undergrounding operation, would be to

dismantle and underground a part of the Roca-Salt 132 kV line (approximately 7 km) along with the EHV

line. This could be taken underground from the C-25 as far as the Riudarenes substation. Energy

compensation and the overhead powerline/underground cable transition would take place at a

compensation substation. This would not involve any significant increase in the visual impact, given the

small surface area, and taking into consideration application of the most appropriate technologies and

corrective and landscaping measures as described in [8]. One alternative to the initial proposal for the

Riudarenes branch would involve continuing the EHV power line tunnel, combined with the 132 kV line, as

far as Riudarenes, and then continuing along the AP-7 corridor, followed by the high-speed railway. This

option would allow more kilometres of the line to be combined, and would exploit the existing

infrastructure in full.




24 24







25

END OF SECTION COMPACTATION A-2/A27

BESCANÓ - STA. LLOGAIA D’ALGUEMA SECTION

BORDILS, CELRÀ AND MEDINYÀ VARIANT

Underground to be determined according to EI.

Brugant-Ter Corridor (N141a)

Bascanó-Salt Section (Pk106+200-112+00)

Underground to be determined according to EI.

Brugant-Ter Corridor (N141a)

Bascanó-Salt Section (Pk106+200-112+00)




26

RIUDARENES BRANCH

LEGEND

EHV LINE: BESCANÓ –JUIÀ

STA. LLOGAIA AND RIUDARENES BRANCH

REE OVERHEAD LINE:

UNDERGROUND PROPOSAL:

ALTERNATIVE UNDERGROUND BRANCH:

EXISTING ELECTRICAL LINE TO COMPACT UNDERGROUND WITH EHV:

PLANNED INFRASTRUCTURE:

GAS PIPELINE

AP-7

A-2

HSR

C-25

CROSS AXIS RAILWAY

Viaduct

Tunnel

* Illustration of possible routes for underground EHV cables (CILMA option): A - Viaduct route; B – Tunnel or micro-tunnel route; C- Oleodynamic impulse; D – Tunnel; E – Horizontal drilling; F – Trench along forest track. Illustration 3– Outline of the underground EHV power line route in the districts of Girona province, following existing and/or planned infrastructure corridors. Sta. Llogaia d’Àlguema – Bescanó section and Riudarenes branch. Source: produced in-house.

4.5 Legal feasibility

The legal principles presented in this section are expanded upon in depth in the legal study commissioned

in January 2010 by CILMA from E. Ribot, a specialist in this field [11b].

According to the aforementioned study, the conclusion is that it would be possible to demand that the

environmental impact process take into consideration an assessment of the effects of the impact and the

direct and indirect costs derived from the installation of electrical power lines. It is thus argued that

consideration must be given, in authorisation for the EHV Powerline Plans for the district of Girona, to the

various studies commissioned by CILMA regarding the overall feasibility of a fully underground solution.

Article 1 of Royal Legislative Decree 1/2008, of 11 January 2008, requires that environmental impact

procedures perform a due assessment of the direct and indirect impacts of a project on human beings, the

air, the climate, the landscape and material property. Meanwhile, Article 7 of Royal Legislative Decree




27

1/2008, on environmental impact studies, requires an assessment of the foreseeable direct and indirect

consequences of the plans. It is the environmental bodies which are empowered to impose the scope and

level of detail of environmental impact studies, in accordance with the terms of Article 5.b of Royal

Legislative Decree 1/2008, of 11 January 2008, and Article 7.1 of the same legal text.

In exercising these powers environmental bodies may require that the process of conducting the

environmental impact study include a specific assessment and analysis of the following indirect costs and

effects:

- Loss of value of properties and buildings affected by the route of the electrical power line;

- Deforestation and loss of wooded areas, with a reduction in CO2 absorption capacity;

- Impact on safety in the region, and hazards;

- Risk of fire;

- Electromagnetic fields and possible direct or indirect impact on health;

- Loss of virgin landscape;

- Impact on birdlife;

- Direct and indirect economic costs.

The Department of the Environment and Housing, as the environmental body responsible for the process of

authorising the installation of electrical power lines in Catalonia, and the Spanish Ministry of the

Environment and Rural and Marine Areas, are both entitled to demand that the environmental impact

study specifically take into consideration underground options. If an analysis of all impacts (indirect costs

and effects or underground options) is not included, either in the public disclosure or consultation phases,

this could be claimed to be irregular, and the plans could be challenged in the decision-making and

authorisation process on the basis of an inadequate environmental assessment.

Quantification of the loss of value of properties and estates as a result of the installation of an overhead

electrical power line has been recognised on several occasions in court judgements handed down both

by the High Courts of Justice of Catalonia and the Spanish Supreme Court. This recognition has applied to

properties directly affected by the route, giving rise to compensation on the basis of the negative effects of

the visual or landscape impact caused, with percentages ranging from 10% to 40%, and even higher, in

accordance with the specific case under analysis.

The possibility of applying "existential value" in environmental assessment processes may, indirectly, be

based on the terms of Article 4.1 of the National Natural Heritage and Biodiversity Act, and Article 45 of the

Spanish Constitution, along with academic theory and the opinions of numerous authors and

commentators cited in the legal report [11b].

It should be pointed out that the Electrical Sector Act (Act 54/97) and Royal Decree 1955/2000 lay down a

series of limitations on the imposition of rights-of-way for high-voltage electrical power lines, limitations

which could be of particular interest in underpinning the requirement for infrastructure and highway

corridors to be employed. Article 57 of the aforementioned 1997 Electrical Sector Act prohibits the routing

of high-voltage power lines over buildings, courtyards, schools, gardens, allotments and sports fields. This




28

article, along with Article 161 of Royal Decree 1955/2000, establishes the preferential use of public

ownership, usage for service areas for the routing of electrical power lines, usage which must take priority

over the employment of privately owned properties, wherever technically and economically feasible.

These arguments and legal limitations could be cited in order to demand a routing of the EHV parallel to

the AP-7 or other existing highway infrastructure routes, installing the power line on publicly owned or used

land and the rights-of-way covered by highways, constituting an infrastructure corridor.

Articles 12 and 13 of the Catalan Natural Spaces Act (Act 12/85, of 13 June 1985) demand the utmost

respect for the landscape in the installation of high-voltage electrical power lines. Article 13 in particular

requires that plans and projects for the electrical transmission grid "select from among the viable options

that which represents the lowest visual and ecological impact". This principle takes on particular

significance in those cases where undergrounding is technically feasible, in cases of impacts on natural

spaces, given that this option undoubtedly represents the lowest visual and ecological impact, by

minimising and practically eliminating impacts on the landscape, risks to birdlife, the risk of forest fires and

deforestation.

The executive summary of the 2006-2015 Catalan Energy Plan makes specific reference, on page 37, to the

possibility of the undergrounding of the EHV power line or the electrical interconnection with France, and

requires that consideration be given to an accurate assessment guaranteeing the minimal environmental

impact. It literally reads as follows: "This option must in all events take into consideration an accurate

assessment guaranteeing minimal environmental impact, without disregarding any possible route,

including the possibility of undergrounding".

4.6 Economic feasibility

The report [9] estimates the direct costs of the underground proposal, specifying overall civil engineering

prices depending on the method of installation. These costs have been supplemented by means of the

economic offer presented by General Cable [10], allowing for calculation of a price per kilometre of the

recommended cabling, including materials8.

There then follows a summary in

Installation method – Price (€M/km)

Directly in trench

In trench with pipes

Concrete box

Other methods: Horizontal directed drilling, oleodynamic pressure, tunnels, etc.

8 It should be pointed out that the cost of the main cable material, namely copper, is subject to considerable fluctuation.




29

a factor of 2, rather than 6 (see Table 2).

ary of overall costss

ngth (km)

Table 1 of the direct costs established depending on the installation method.

Installation method – Price (€M/km) Directly in trench

In trench with pipes

Concrete box

Other methods: Horizontal directed drilling, oleodynamic pressure, tunnels, etc.

Table 1 – Summary of estimated direct costs in accordance with the installation method considered. Source [9].

According to the report [9], the ultimate conclusion is that undergrounding the EHV line in the districts of

Girona province would cost approximately 6 times more than REE's overhead solution if one takes into

consideration only the investment costs.

The economic study undertaken by the University of Girona in report [6] calculates not only the direct costs

or civil engineering costs, but also performs an estimate of the aforementioned indirect costs. These indirect

costs include: loss of well-being on the part of the population affected by the infrastructure through

expropriation, loss of value of land and housing affected, impact on economic activities connected with

tourism, landscape impact, etc. In this regard the University of Girona study places an approximate value

of €2M/km of losses on average in the value of property (land and housing) affected by the overhead

route. The costs of operation, maintenance and dismantling of power lines have also been added in, in

accordance with the bibliography consulted [21]. This then gives us what we refer to as the "overall costs"

of the new infrastructure.

If one takes into consideration all these costs, according to report [9] and report [6], the difference

between the cost of the overhead solution and the underground solution is reduced considerably, down to

Table 2 – Summestablished for the EHV power line as a whole in the districts of Girona province. Source: [9].

Le

Direct expenses

Global expenses




30

l cost of undergrounding in the district of Girona province is estimated at €8M/km. The

When Commissioner

embered that the two direct current/alternating current conversion

ther items valued as improvements include:

ting 132 kV power lines would represent an increase of 6% in

lanned substations would, according to report [9] involve an

4.7 Sociopolitical feasibility

conomic arguments presented, past experience demonstrates that the

and above technical or economic considerations, has been clearly expressed in the

eloped societies tend increasingly to take into consideration the

The direct and overal

direct cost of the overhead solution is estimated at €1.6M/km and the overall cost estimated at €4M/km.

The difference in the overall cost of the two solutions would stand at around €4M/km.

One further calculation must be added in to these figures in terms of existential value.

M. Monti recommended that the direct current section should be undergrounded in the Pyrenees, he

attributed an indirect existential value of more than €18M/km. This is the sum that the EU was prepared to

pay to safeguard the Pyrenees from the impact of an overhead EHV power line, or their existential value. It

should be remembered that the direct cost of the interconnection was estimated at €20M/km (including

the two DC/AC conversion substations). In this regard, if the districts of Girona province were attributed an

existential value just one quarter of the value which the EU placed on the Pyrenees, the best option would

then be to underground the EHV.

It should meanwhile also be rem

substations will cost around €600M. This figure, which does not take into consideration increases as a result

of undergrounding, is in itself greater than the initial increase in investment estimated as a result of

undergrounding the EHV line as a whole in the districts of Girona province.

O

- The dismantling and combination of the exis

the overall direct cost of undergrounding;

- The use of GIS technology for all the p

increase of 5% in the total direct cost of undergrounding.

Despite the technical and e

decision whether or not to underground infrastructure of this type is impossible without the relevant social

and political will.

Political will, over

decision to install the Baixàs- Santa Llogaia direct current interconnection underground, since on this

section the technical experts in electrical matters agree that it is not the most desirable solution from the

technical and economic perspectives.

The political decisions adopted by dev

indirect costs of the infrastructure and preservation of the environment.




31

5 - DGEM COMMISSIONED ASSESSMENT REPORTS

The ERF report that compares the environmental impact of underground cables and overhead lines

displays a lack of and confusing information, which discredits its main conclusions:

- In analysing the impact of undergrounding, it does not choose the option schematically defended by the

CILMA report (version November 2009), wherein the underground EHV transmission line runs alongside the

merged AP-7/A-2 and the A-2 widening, but, instead, tendentiously follows the course of the High-Speed

Rail, which traverses a larger forested area and more complex orography. Therefore, the assessment on the

effect undergrounding has on forested strips proves inflated and false;

- With respect to the trench solution discussed in the ERF study, let it be said that only a 100% trench solution

was considered. This is highly unrealistic, as, in reality, alternate construction methods must also be weighed

to pass underneath singular sites such as rivers, roads or railway lines. Fully cognizant of the exceptional

nature of undergrounding cable in gallery across large distances, CILMA proposed and budgeted to

possibly underground cable in gallery over most of the Bescanó-Sta. Llogaia section, mainly due to the

proposal to compact other high voltage (HV) lines in the same gallery, and the fact that a box could be

inserted perfectly into the AP-7 easement, already affected by a series of restrictions. The trench option

was evidently not discarded, as it is the most widely used method in similar underground installations.

- CILMA’s proposal does not affect wooded masses whatsoever, given that it makes use of the A-2 and

merged A-2/AP-7 service roads. In the odd instance where this is not possible, the flexibility inherent in

undergrounding underground cables means that wooded masses can be easily averted;

- In comparing impact, the report stated that the overhead line’s visual effect was akin to that of the

underground cable trench, irrespective of the fact the latter will be covered by either the A-2 or the

merged A-2/AP-7 service roads, or a pasture, field or brush, blending in perfectly with the mosaic of the

plain’s rural landscape. It is absurd, therefore, to compare the visual effect of successive up-to-90-metre-

high towers with that of an invisible line that blends in with the landscape.

- It also stated that both the overhead and underground options had a similar impact on avifauna. This is

out of line, as undergrounding has no perceivable effect on forested areas, and especially because it is a

known fact that overhead power lines, whether low, medium, high or extra high voltage, represent one of

the main causes of reversion for certain endangered species, albeit nesting or migratory birds;

- The ERF analysis applies a criterion that wholly conditions the parametric assessment’s final results: it

affords the same weight to the duration of the construction phase impact as that of impact produced

during the production phase. While the impact caused during the construction phase by undergrounding is

evidently superior to that generated by installing the overhead line, the situation reverses during

production. What’s more, over time, the latter’s impact extends much further. Thus, in calculating the

accumulated production-phase impact, the negative effects of the two options must be multiplied

(something reasonable would be by 30 years), thus yielding distinct results: exactly the opposite;




32

- The COEIC report does not provide any foundation that refutes the viability of undergrounding the EHV

alternating current transmission line between Bescanó and Santa Llogaia d’Àlguema or the branch

transmission line to Riudarenes:

It does not question whether the technical solutions established in the CILMA reports are applicable to the

specifications inherent in undergrounding with alternating current through these sections;

- Nor does it debate whether the electric power system in the undergrounding option is functional or

viable;

It still postulates over the need for the EHV line, a discussion in which CILMA has never participated;

- It only assesses a number of overhead power line scenarios that were listed in a preliminary report

obtained by CILMA in 2007. It does not discuss the contributions made in the 2009 synthesis, which included

an extensive collection of multi-disciplinary technical documents with accumulated information on various

fields (electrical, construction, territory, landscape, social, environmental and economic);

6 - PROOF

The erection of a new overhead EHV line is not compatible with a territory with a dense urban

outspreading or, to a much lesser degree, with a diverse, fragile landscape, its principal economic asset.

Undergrounding the EHV transmission line along the merged AP-7/A-2 and, outside this stretch, the A-2

widening is completely feasible, making use of the service roads that must be constructed regardless and,

in particular, the empty space generated between the parallel courses of the AP-7 and A-2.

Infrastructural opportunities appear throughout the entire route over which undergrounding is being

defended, whereby infrastructures are either under construction or must be constructed, as with the AP-7,

A-2, N-141 (Brugent-Ter), the HSR, C-25 (transversal road), the oil pipeline and the Catalonia Transversal

Railway Line.

Undergrounding the EHV transmission line in the plain also presents an opportunity to underground existing

high and medium voltage overhead lines that have the same line routes. To be precise, this document

proposes that the following lines be compacted with the EHV transmission line via gallery:

- FECSA 132 kV HV DC transmission line (20km) Juià –Figueres;

- HV transmission line Salt - La Roca (7km).

Undergrounding the EHV will help curb the existing overhead power lines’ impact, thereby increasing and

restoring the landscape’s value in a territory that depends on it. This positive impact must be assessed and

accounted for economically when calculating indirect costs.

The installation of underground cable in the plain is minimised and blends in perfectly with the rural

landscape, as it makes use of the service roads of infrastructures currently under construction and is,

furthermore, compatible with agricultural fields, pastures, wooded terrain, rail trails and rural paths.




33

The underground cable’s electromagnetic field is greatly reduced, concentrated above the cable only.

This makes the line route flexible, helps avoid urban outspreading and, therefore, nullifies negative effects

on people’s health.

The European Institutions’ previous decision to underground the cross-border section must be taken into

account. With the ERF report’s assessment system in mind, the impact of undergrounding the cross-border

section would be much greater in comparison to overhead lines, given, firstly, the environment’s irregular

orography, whereby undergrounding cable proves more complex, and, secondly, the breadth and density

of the forested mass, which increments its impact on natural systems.

The COEIC report does not demonstrate that undergrounding cable along the infrastructure corridor is not

unviable; it does not refute the technical solutions that could be applied to resolve the singular issues

inherent in undergrounding.

The specifications inherent in undergrounding cable in the plain are much less conditioned and

demanding, or rather, much easier to resolve, than the enormous technical difficulties caused by

conversion to direct current in the cross-border section.

As acknowledged in the ERF report, the cost of undergrounding cable in the plain is akin to the price of but

one alternating to direct current converter substation, of the two that are anticipated, in the already

approved undergrounding of the cross-border section. In other words, pursuant to the very same ERF

report, undergrounding cable in the plain will cost five times less than undergrounding the cross-border

section. Thus, the cost of undergrounding cable in the plain is well within reach, and when compared to

the electric power transmission and distribution companies’ economic profits (REE and Entel), it is in no way

significant.

The vulnerability of overhead power lines in the face of storms, atmospheric phenomena that, due to

climate change, will only intensify, has been well demonstrated.

The marked trend in favour of undergrounding options must be emphasised, and not only within urban

settings, but in rural surroundings as well. In July 2009, the French National Assembly proposed a new law

(No. 1820) that limits the impact of high and extra high voltage transmission lines over the land and over its

inhabitants. This proposal is currently being studied by the corresponding commission (Sustainable

Development and Spatial Planning Commission). Elsewhere, in an effort to reduce the public transmission

grid’s environmental impact, the RTE is committed, having signed a Public Service Contract with the French

Government, to:

Underground at least 30% of new or renovated HV circuits;

Eliminate the same number of kilometres of existing overhead lines as newly-constructed or re-constructed

overhead lines.

Along these lines, to compensate the presence of the Cotentin-Maine overhead EHV transmission line,

163km of existing HV overhead lines will be eliminated from the surrounding area and 105km of the power

lines projected for the affected towns will be undergrounded. All together, almost double the length of the

Cotentin-Maine transmission line will be undergrounded.




34

7 - CONCLUSIONS

With the cited references and according to the synthesis herein presented, this document has provided

arguments to demonstrate that undergrounding the EHV transmission line in the counties of Girona is both

possible and viable, from a technical, constructive, economic, territorial, environmental and socio-political

perspective.

A number of sections have been sized to install 12 2500mm2 cables with XLPE insulation, which,

undergrounded, would have a capacity equivalent to the overhead solution. Losses have been estimated

in different load situations and the reactive power compensation that the undergrounding requires has

been quantified. A proposed route has been presented at 1/30,000 scale, which makes use of the

territory’s existing infrastructure corridors, and conceptual execution solutions that avoid all obstacles have

been provided. Environmental sensitivity and the impact caused by the two solutions herein compared

have also been studied.

Finally, it was estimated that the underground solution’s direct costs are 6 times higher than those

attributed to the overhead solution. However, taking into account that an underground line incurs less

maintenance costs and power losses than an overhead line, and, moreover, bearing in mind the indirect

costs, such as land devaluation, the difference between the two solutions decreases to a factor of

approximately 2. Yet, if we take into consideration the existence and bequest values inherent in a possible

Pyrenees interconnection, this factor reverses, and thus the underground option could prove to be the

most economical.

CILMA defends the execution of an underground construction project that takes contributed elements into

consideration. Competent technicians and up-to-date technologies are available to study and solve the

singular features of a leading, avant-garde and model project, which would, furthermore, foment

technological advancements and, in a complementary manner, help revitalise the construction industry.

8 - LIST OF THE PRINCIPAL EXPERTS AND TECHNICIANS CONSULTED

TECHNICAL ASPECTS:

- Daniel Dépris, Physicist, European expert from the CSHP-ERO9 and OCPE10, President of CEPHES11;

- Jordi Monteys, PhD Industrial Engineer from Taller d’Estudis PALOP;

- José Maria Giménez, PhD Industrial Engineer from Taller d’Estudis PALOP;

- Josep Puig, PhD Industrial Engineer and Professor at the Universitat Autónoma de Barcelona;

9 Conseil supérieur d’hygiène publique – European Radiocommunications Office 10 Office communautaire de formation et d’enseignement 11 Comité Européen pour la Protection de l’Habitat, de l’Environmment et de la Santé




35

- Jacint Rovira, Technical & Commercial Director of General Cable;

- Antoni Trisan, Technical & Commercial Engineer from General Cable;

- Bàrbara da Silva, Civil Engineer (Roads, Canals and Ports) from MOST Enginyers, Ltd.

- Jordi Mulà, Industrial Engineer, Second Vice-President of CILMA and Head of the Energy Efficiency and

Renewable Energy Commission;

- Laura Mascort, Industrial Engineer.

ENVIRONMENTAL ASPECTS:

- Jaume Hidalgo, Forest Engineer, Coordinator of Environment and Territory for the Girona Regional Council

and Technical Secretary of CILMA;

- Marc Marí, Biologist and Head of Environment and Territory for the Girona Regional Council;

- Judit Vilà, Environmental Scientist and Environmental Technician at CILMA;

- Salvador Oliva, Technical Agricultural Engineer of Environment and Territory for the Girona Regional

Council;

- Bàrbara da Silva, ECCP and M.Sc. in Environmental Sciences and Technology, MOST Enginyers, Ltd.

- Mr. José Luis Bardasano Rubio, PhD in Biological Science, Licentiate in Medicine and Surgery, Specialist in

Bioelectromagnetism. President of the European Foundation of Bioelectromagnetism and Health Sciences

and Advisor to the Congress of Deputies’ Environmental Commission.

ECONOMIC ASPECTS:

- Anna Garriga, PhD in Economics and Dean of the School of Economic and Business Sciences at the

Universitat de Girona.

LEGAL ASPECTS:

- Eduard de Ribot Molinet, Lawyer;

- Pere Monteagudo, Lawyer.

POLITICAL REPRESENTATION

- Lluís Lloret, President of CILMA;

- Jesús Llauró, First Vice-President of CILMA and Head of the Infrastructure Commission;

- Jordi Mulà, Second Vice-President of CILMA and Head of the Energy Efficiency and Renewable Energy

Commission.




36

9 - REFERENCES

REFERENCES OF COMPLETED AND ATTACHED STUDIES AND REPORTS

[1] “Estudi d’alternatives de les Línies Elèctriques d’Alta Tensió Bescanó-Riudarenes i Bescanó-Santa “, IM3 ,

Ingenieros Emetres Ltd., November 2006.

[2] “Estudi dels valors naturals, paisatgístics i patrimonials en l’àrea afectada pel projecte “Línia elèctrica a

400kV d’entrada i sortida a la subestació de Riudarenes des de la línia Sentmenat-Vic-Bescanó”, Fractàlia

Consultoria i estudis ambientals Ltd., May 2007.

[3] “Annex a la Valoració del Medi Natural, patrimonial i paisatgístic a l’entorn del traçat de la MAT i la

subestació de Riudarenes i de Bescanó:Redacció de conclusions”, La Copa, May 2007.

[4] “Rapport préliminaire relatif à la restructuration des réseaux THT-EHT de Catalogne dans la perspective

du TGV Perpignan-Barcelone”, Daniel Dépris, November 2007.

[5] “Informe sobre experiències de soterrament de línies de molt alta tensió, Josep Puig i Boix” , Dr. Eng.

Industrialist and UAB Professor, 2008.

[6] “Informe de viabilitat tècnico-econòmica del soterrament de la línia d'alta tensió en el corredor

d'infraestructures de Girona. Tram Bescanó-Santa Llogaia i ramal de Riudarenes”, Fractàlia, July 2008.

[7] “Informe sobre la viabilidad de canalizar mediante cable aislado enterrado la línea de 400kV Santa

Llogaia-Bescanó y el ramal de Riudarenes”, José Ma Giménez Tresaco and Jordi Monteys i Viñals, Taller

d’estudis PALOP, May 2009.

[8] “Estudi de minimització dels impactes ocasionats per les subestacions de la MAT a les comarques

gironines”, MOST Enginyers Ltd., January 2009.

[9] “Informe tècnic sobre les alternatives de soterrament de la línia de molt alta tensió entre Santa Llogaia

d’Alguema - Bescanó i ramal de Riudarenes – traçat i obra civil”, Most Enginyers Ltd., May 2009.

[10] “Technical and Economical Offer”, SILEC (General Cable), June 2009.

[11a] “Legal report – viabilitat de soterrament de la línia MAT per les zones d’afectació de les

infraestructures existents”, E. de Ribot, July 2009.

[11b] “Estudi de la viabilitat jurídica de soterrament de línies elèctriques”, E. de Ribot, February 2010.

[29] “Informe d’Avaluació de l’estudi d’afectació territorial i valoració ambiental i econòmica del

corredor elèctric Bescanó-Santa Llogaia i del ramal de Riudarenes redactat per Estudi Ramon Folch al

febrer de 2010 per la DGEM”, MOST Enginyers Ltd., April 2010.

RECOMMENDED AND CONSULTED WORKS

[12] “Large Projects of EHV Underground Cables Systems”, A-21, Jicable, 2007

[13] “The St. Johns Wood – Elstree Experience-Testing a 20km long 400kV XLPE-Insulated Cables System After

Installation”, A-22, Jicable, 2007

[14] “Undergrounding and Reorganization of the Electrical System of the City of Madrid”, A-25, Jicable,

2007




37

[15] “Performance of Modern Cables in Central Europe”, C-514, Jicable, 2007

[16] “Statistics of AC Underground Cables in Power Networks”, Brochure 338, CIGRE, December 2007.

[17] “400kV Underground Cables in Rural Areas”, CIGRE B1-211, 2006.

[18] “A New Procedure to Compare the Social Costs of EHV-HV Overhead Lines Underground XLPE

Cables”, CIGRE B1-301, 2006.

[19] “Comparison of High Voltage Overhead Lines and Underground Cables”. Brochure 110, CIGRE, 1996.

[20] “The Highland Council, Cairngourms National Park Authority & Scottish Natural Heritage

Undergrounding of Extra High Transmission”.

[21] “Réseaux électriques souterrains, immergés et sous-marins”, Daniel Dépris, 1998.

[22] “Analyse de besoins pour une nouvelle interconnexion entre la France et l’Espagne. Cahier 2”, M.

Monti, March 2008.

[23] “Undergrounding of Electricity Lines in Europe”, Background paper, European Commission, December

2003.

OTHER REFERENCES

[24] “Estudi d’afectació territorial i valoració ambiental i econòmica del corredor elèctric Bescanó-Santa

Llogaia i del ramal de Riudarenes”, Estudi Ramon Folch (ERF), February 2010. (commissioned by the DGEM).

[25] ”Disseny i construcció de línies d’alta tensió. Benchmarking mundial”, ERF, January 2010.

[26] “Anàlisi i diagnosi sobre la viabilitat del soterrament de la línia elèctrica a 400kV Bescanó – Ramis -

Santa Llogaia”, COEIC, Febraury 2012.

[27] “Informe sobre la solicitud de autorización administrativa y declaración de impacto ambiental de la

línea eléctrica de 400kV Bescanó-Subestación Ramis-Subetación Santa Llogaia; así como de la solicitud

de autorización administrativa, declaración de impacte ambiental, aprobación del proyecto ejecutivo y

declaración de utilidad pública de las subestaciones Ramis y Santa Llogaia”, General Director of Energy

and Mines for the Generalitat de Catalunya, November 2009.

[28] “Informe línea Eléctrica a 400kV-50Hz Sentmenat-Bescanó y Vic-Bescanó”, Mr. José Lluis Bardasano

Rubio.

APPENDIX: SUMMARY TABLE

Underground tunnelling viability in an alternating current with an isolated XLPE cable in the 400kV double circuit

Very High Voltage line to the regions of Girona Sintesi_refos_taules.doc

Tables - Summary document outlining main issues Page 1 of 5

OVERHEAD LINES BURIED CABLES INSTALLATION SAFETY

- Danger of electrocution and electrification: registered accidents with farmers, sailing boats, etc. - Significant fire risks. - Very exposed to the elements, vandalism and possible terrorist acts.

- No risk of electrocution accidents. - Does not cause fires. - Protected and safe installations.

VISUAL AND ENVIRONMENTAL IMPACT

- Significant visual impact. Lattice tower placement every 500m and around 55m high. - Plotted in wooded areas coupled with corridor deforestation of approximately 33m. - Tower access required for maintenance.

- Almost nil; no visual intrusions. Totally integrated to the landscape. - Plotted in existing infrastructure corridors. Easy to access surface boxes. - Passage corridor according to installation method: approximately 4m in the gallery and between 8 - 12m when flush with a trefoil or horizontal layout, respectively. - Width temporarily affected by the works between 10 and 15m. - Recovery once 18-24 months pass after works; impact of works reversible and temporary. - Need to install joint boxes (underground) that may be visited between 500 and 850m.

FAUNA - AVIFAUNA IMPACT

- Significant electrocution danger, especially to birds of prey. - Storks that do not have very developed vision are also affected. - “Every year, EDF/RTE overhead lines kill more birds than those killed by French and Navarre hunters combined", D. Dépris [4]

- No impact. Prevents electrocution danger, shock and death of birds.

1




ELECTROMAGNETIC FIELDS

- Significant electrical and magnetic fields.

- Nullification of electrical fields. - Near-nullification of magnetic fields when adopting trefoil installation method (depending on distances between phases).

ACCESS - Need to access towers every 500m, mainly located in wooded and hilly areas.

- Need to access joint surface boxes located every 500 to 850m. - Easy to access as they follow other infrastructure.

GROUND USE - Affected area is larger. - Special care when using machinery near lines. - Incompatibility with agricultural activities with long- or medium-stemmed fruit tree production.

- Less affected width; - Conservation of original use (except planting trees). - Less affected area to private persons due to route (flexibility and use of infrastructure protection zones). - Possible social use of new corridor - for example, rail trails. - In wooded areas or in the event of a fire, they act as a firewall.

IMPACT DUE TO WORKS

- Creation of access tracks in wooded areas; - Faster construction and less civil work provision.

- Works last longer; - The route allows for minimising temporary disturbances of work; - The gallery or the flush installation with concrete pipelines allows for civil work and cable spread to be independent: minimisation of necessary affected area and width. - Flush installation with concrete pipelines supports heavy transit loads: minimises the need to occupy parallel corridors during construction.

2




CLIMATIC VULNERABILITY

-Destructive effects of the wind: wind resonance phenomenon in towers or stronger than predicted winds; - Breakage, sinkage, ice overload, asymmetry of loads.

- Invulnerable to harsh climatic conditions.

FIRE RISKS - Significant fire risks in forests: unusually high losses due to isolation deficiency; - A particularly sensitive issue in Catalonia with uncontrollable periods of drought and forest fires.

- No risk of fire. - Positive effect on passage corridor, that acts as a barrier in case of fire.

ENERGY SAFETY - Completely exposed and vulnerable to vandalism and terrorist acts; - Possible large-scale socio-economic disorders.

- Protected and difficult-to-access installations.

NOISE POLLUTION - Harmful health effects due to ionisation of the air (corona discharge). - It can be particularly felt in areas when noise levels are generally low, in rural areas as is the case here.

There are no repercussions.

CHEMICAL POLLUTION

- Pollution due to corona discharge (ionisation of the air). - May cause discomfort to people with sensitive respiratory tracts and eyes.

- There are no repercussions

LOSS OF PROPERTY VALUE

- Significant indirect expense: loss of property value of goods; - According to UdG study, cost associated with 400kV overhead line is €2M/km.

- There is almost no loss. - In addition, the route is more flexible and can miss properties.

3




FUNCTIONALITY, MAINTENANCE AND EXPLOITATION

- Sensitive to atmospheric agents. - Loss of energy 3 times more significant when in a maximum load situation. - Maintenance hard as difficult to access towers. - Constant transitional faults and possible automatic reconnection. Faults two times more probable: 0,170 per 100 circuits km/year. - Conductor, joint and isolation surveillance and maintenance. - Easier enlargement and proliferation.

- Immune to atmospheric agents. - Less energy loss in load situation, implies decrease in operational costs and energy production. - It becomes easier and quicker to repair a breakdown and they are not very frequent. Least probable faults: 0,072 per 100 circuits km/year. - Tunnel construction - gallery, the joint boxes and the conductors allow for immediate access for reparations without the need to open flush systems. - RTE adopts special measures and favours burial of lines after weather exposure in December 1999, in France; - Quality control of joints is the guarantee of their reliability. - Periodic surveillance and maintenance of joint chambers. - Extensions must be previously planned. - Consistency of environmental features. - Reparation time generally longer. Solely damaged circuit unavailable.

REACTIVE ENERGY Compensation not required. - Substations require compensation. - Improvement of compensation technology and reduction of associated space and expenses. - Intermediary substations not required. - Main interconnection experiments in Gulf states and in Shin-Toyosu in Japan.

4




EXPENSES

-Lower indirect expenses (6 times); - Handling fees, maintenance and loss of energy most important; - Indirect expenses assessed as very important (expropriation, loss of property value): €2M/km - Other very important indirect expenses difficult to quantify: environmental, climatic, and those due to accidents. - The existence and inheritance value is not considered in the affected region when this solution is chosen.

- Higher direct expenses (6 times) - handling fees and maintenance almost nil. - Insignificant indirect expenses. - Energy loss expenses are less on a global scale. - Global expenses (quantifiable) 2 times higher (without considering others such as existence and inheritance value) - If existence and inheritance value of the region is considered, global expenses would be less than for an overhead line.

5

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